PCT Application No. PCT/CA2011/001294, incorporated herein by reference in its entirety, teaches the use of an apparatus conforming to the surface of an anatomical region to attach one or more rigid bodies to the anatomical region at a repeatable position relative to the anatomical region. Such repeatable fixation may enable geometrical mapping of anatomical regions across clinical procedures performed at different times. For example, during a surgical procedure, an anatomical region may be dynamically registered with an image of the anatomical region to provide guidance to the surgeon. As well, the range and patterns of motions of anatomical regions may be measured and compared. Furthermore, the anatomical region may be repositioned relative to an instrument for various forms of treatment.
PCT Application No. PCT/CA2015/050025, incorporated herein by reference in its entirety, teaches a moldable appliance containing a rigid fiducial body that includes a plurality of feature regions and that defines a fiducial plane. PCT Application No. PCT/CA2015/050025 describes a fiducial body embedded in the moldable portion, and having the complete appliance, including the fiducial body, molded and attached to the jaw both during scanning and during surgery.
Prior designs may have a number of important drawbacks. For example, it can be difficult to mold the appliance directly in the patient's mouth, in particular for the lower jaw, because the patient's lips may apply a substantial force pushing the appliance off the jaw. Users may also find it difficult to hold the jaw-facing surface tight against the teeth while the appliance is hardening. Similarly challenges may arise during surgery, where the force of the patient's lips may lift the appliance off its seating on the teeth. Furthermore, some prior designs include fiducial bodies having exposed sharp corners that may cause discomfort and pain to patients during fabrication.